TI  - Identification of a <prot><prot>gp130</prot> cytokine receptor</prot> critical site involved in
      <prot>oncostatin M</prot> response.
PG  - 5648-56
AB  - <prot><prot>Gp130</prot> cytokine receptor</prot> is involved in the formation of multimeric
      functional receptors for  <prot>interleukin-6</prot> (<prot>IL-6</prot>) , <prot>IL-11</prot> , <prot>leukemia inhibitory
      factor</prot> (<prot>LIF</prot>)  ,  <prot>oncostatin M</prot> (<prot>OSM</prot>) ,  <prot>ciliary neurotrophic factor</prot> , and
       <prot>cardiotrophin-1</prot>  . Cloning of the epitope recognized by an <prot>OSM</prot>-neutralizing
      anti-<prot>gp130</prot> monoclonal antibody identified a portion of <prot>gp130 receptor</prot>
      localized in the EF loop of the cytokine binding domain. Site-directed
      mutagenesis of the corresponding region was carried out by alanine
      substitution of residues 186-198. To generate type 1 or type 2 OSM
      receptors, <prot>gp130</prot> mutants were expressed together with either <prot><prot>LIF</prot> receptor
      beta</prot> or <prot><prot>OSM</prot> receptor beta</prot>. When positions Val-189/Tyr-190 and
      Phe-191/Val-192 were alanine-substituted, Scatchard analyses indicated a
      complete abrogation of <prot>OSM</prot> binding to both type receptors. Interestingly,
      binding of  <prot>LIF</prot>  to  type 1 receptor  was not affected, corroborating the
      notion that in this case <prot>gp130</prot> mostly behaves as a converter protein
      rather than a binding receptor. The present study demonstrates that
      positions 189-192 of <prot>gp130</prot> cytokine binding domain are essential for <prot>OSM</prot>
      binding to both  <prot>gp130</prot> / <prot><prot>LIF</prot> receptor beta</prot>  and  <prot>gp130</prot> / <prot><prot>OSM</prot> receptor beta</prot> 
      heterocomplexes.
AD  - INSERM E 9928, CHU d'Angers, 49033 Angers Cedex, France.
